Z-Machine at Sandia Labs Aims for More Power

Vexar writes "Memorable for its Back-to-the-Future room of electric arcs in 1998, Sandia Labs' Z-Machine is getting $61.7 Million in new funding. In addition to more physics textbook-worthy photos, the scientists at this lab intend to hit the all-important, fusion-ready 2.0 million degrees C."

Comments

Re:Weapons research

[deglr6328]

Jim you're on my slashdot friends list but I'm afraid I must completely disagree with you here. :o)

Tokamaks have problems, yes, but I don't think it's known weather these problems will prohibit their utilization as a fusion power source. For instance if a plasma instability forms in a tokamak while running (happens all the time) and the plasma bumps the divertor or the inside of the chamber it most certainly will not be bomb like and won't "result in burn-through" either. The introduction of (relatively) high Z material (carbon from graphite, iron, or aluminum from chamber walls) will result in INSTANT plasma quenching via the plasma radiating a huge portion of its energy through bremsstrahlung. This causes burn marks and other dust problems in the chamber but can't cause burn through of the thick metal vacuum chamber walls. And if there is a catastrophic breach of the plasma vessel it definitely, DEFINITELY will never be anything even close to a "chernobyl-style quarantine". At most, a couple grams of radioactive tritium (3-hydrogen) are contained in the vessel while "burning", even considering a total failure of containment and burnoff (a small explosion, to be sure) of all the hydrogen to form tritiated water (forming molecules of TOH or TOT rather than HOH) the amount of radioisotope release will be in the tens of KiloCurie range. Tritium is the least dangerous radioactive isotope that exists (I work with it daily), with a ~12 year half life and an average beta particle emission energy in the 5KeV range to a max of 18KeV, barely enough to go a few mm in air before being blocked; and owing to the fact that both hydrogen and water are volatile, it will be VERY quickly be evenly dispersed and diluted in the atmosphere and oceans. I doubt anyone working in the plant would die if assuming sufficient containment were used.

Tokamaks do have the issue of neutron activation to worry about among other things but I think these are at least workable problems. Remember, Tokamaks have held the world record for plasma temperatures and containment times for a very long time.

But ultimately you may be right, the Tokamak may prove unworkable from an economic energy generation standpoint. I think the project at MIT using a levatated dipole for more "natural" quiescent plasma containment looks very interesting (promising? maybe), for instance.

All of this said, BIG congratulations to the Sandia Z-machine people!! They deserve it. The energies and powers (~300 Twatts!) they've achieved are barely a factor away from those expected on the finished National Ignition Facility. The lab where I work supplied the parts for the laser called the Z-Beamlet they use to "backlight" targets so they can be viewed in X-rays as they're being imploded on Z. Looks like they've put it to good use. As new technologies like these (and others achieving PETAwatt powers) come online they will open completely new doors to fusion research This is an exciting time for very high energy experimental plasma physics.